Sudanese authorities were working on Monday to free two French and Canadian women aid workers who were kidnapped at the weekend in the increasingly dangerous war-torn region of Darfur."Efforts to free them are under way," foreign ministry spokesman Ali Yussef told AFP. "They are both women."

The two international staff from Aide Medicale Internationale (AMI) were abducted at Ed el-Fursan in southern Darfur on Saturday night, said the French group, which has been targeted twice so far this year.

Two Sudanese AMI staff were also kidnapped and later released, a local official said.

The Sudanese Media Centre, which is close to the country's intelligence services, has said the kidnappers were demanding a ransom, but this was not possible to confirm.

The so far unidentified women were snatched on Saturday night from AMI offices south of South Darfur's capital Nyala, and around 100 kilometres (65 miles) from the border with Chad, a local official said, requesting anonymity.

AMI said it "strongly deplores this kidnapping of members of its team who work daily to improve the health of the local population."

The group, which has been providing medical relief in Ed el-Fursan since 2004, was spared from Khartoum's decision last month to expel several non-governmental aid organisations from Darfur.

"We were continuing our programme, we weren't targeted," said Frederic Mar, a spokesman for AMI.

The French authorities were alerted and the foreign ministry in Paris set up a crisis response cell to deal with the kidnapping, saying it was acting because the incident involved a French organisation.

Canada's foreign affairs department said it was seeking information about the kidnapping.

Two Sudanese workers for AMI were shot dead when their bus was attacked by men on horseback in February in southern Darfur. Four others were wounded in that attack.

On March 23, a Sudanese man working for a Canadian aid group was shot dead at his home in Darfur, reportedly because his attackers wanted his satellite telephone.

Four workers with Doctors Without Borders (MSF), three of them foreigners, were kidnapped at gunpoint from their Darfur home on March 11.

They were all released four days later, with no signs of violence or a ransom being paid, Sudanese and MSF officials said.

That abduction was the first of international aid workers since civil war erupted in Darfur in 2003, and took place just 10 days after the ICC issued the arrest warrant for Beshir.

"This is a very worrying new phenomenon," a source familiar with the security situation in Darfur told AFP, requesting anonymity. "This is a new trend towards humanitarian actors in Darfur."

PARIS/KHARTOUM - Two expatriate staff members of Aide Medicale Internationale were kidnapped at gunpoint in southern Darfur overnight, the French medical aid group said on Sunday.

A U.N. source in Khartoum said unidentified men seized the two international staff and two Sudanese guards from their compound in Ed el Fursan just before midnight on Saturday night. The two guards were later released, the source said.

Sudanese police surrounded AMI's compound on Sunday morning after the kidnapping was discovered.

The French foreign ministry said its crisis centre in Paris had been activated and the French embassy in Khartoum was in touch with the organisation and with local authorities.

Land around Ed el Fursan, about 90 km (55 miles) south west of the South Darfur capital Nyala, has in recent weeks been the scene in an upsurge of fighting between members of the rival Habbaniya and Fallata tribes.

The clashes, rooted in long-standing disputes over land and other traditional rights, have escalated because of the supply of arms that has flooded the area during the six-year Darfur conflict.

Officials for Darfur's joint U.N./African Union UNAMID peacekeeping force said they could not comment on the case while investigations were going on.

Aide Medicale Internationale said it had been operating in Darfur since 2004 in Khor Abache and Ed el Fursan, with a coordination centre in Nyala, supporting clinics and health centres in rural areas.

A spokesman for a faction of Darfur's rebel Sudan Liberation Army (SLA) denied his men, or any other insurgent force, was behind the kidnapping.

"It can only be government militias. They expelled 13 foreign aid groups last month. This is part of the same plan, to empty Darfur of all international organisations," said Ibrahim al-Helwu, from the faction controlled by Abdel Wahed Mohamed Ahmed al-Nur.

Sudan expelled 13 international aid groups from the north of the country in March accusing them of helping the International Criminal Court build up a war crimes case against Sudan's president, an accusation the groups deny.

Sudanese government officials said three foreign workers for Medecins Sans Frontieres kidnapped in March in north Darfur were taken by a group protesting over the ICC's move against Sudanese president Omar Hassan al-Bashir.

Aid groups have said they have faced growing antagonism in Darfur since the ICC issued an arrest warrant for Bashir.

Aid officials said they were worried that the kidnaps might mark the start of a new trend.

"We have had practically everything else - robberies, car-jackings, attacks," said one official. "But the kidnapping of international staff has never been an issue before. (Editing by Angus MacSwan)

Armed men in Sudan's Darfur region kidnapped two aid workers from a French humanitarian group overnight, the organisation said Sunday.

The two team members of Aide Medicale Internationale (AMI) were abducted at Ed al Fursan in southern Darfur, a statement from the group said.

AMI declined to release the names or the nationalities of the aid workers.

"Aide Medicale Internationale strongly deplores this kidnapping of members of its team who work daily to improve the health of the local population," it said.

The AMI team, which has been providing medical relief in Ed al Fursan since 2004, was spared from Khartoum's recent decision to expel several non-governmental organisations from Darfur.

"We were continuing our programme, we weren't targeted," said Frederic Mar, a spokesman for AMI.

French authorities were alerted and the foreign ministry set up a crisis response cell to deal with the kidnapping, saying in a statement that it was acting "given that it was a French NGO" that was concerned.

Two Sudanese workers for AMI were shot dead when their bus was attacked in in February in southern Darfur.

“Violence will bring no victory. For the sake of the Darfur civilians, all parties to the conflict have to stop resorting to violence. This is the absolute priority.” - Luis Moreno-Ocampo, Prosecutor of the International Criminal Court, 05 June 2009

"APPREHENSION" by Rob Rooker. Painted on a wall in Maridi, Sudan. The image is of a young Nuer boy looking up among a crowd of people. Click on image for more details. Cards & prints of Rob's paintings can be purchased online at Imagekind.com